Updated September 6, 2025 at 9:35 AM CDT
President Trump signed an executive order on Friday to give the Department of Defense a new name: the Department of War.
Speaking from the Oval Office, Trump said the rebranding reflected a new tone for the country and its military.
A White House fact sheet explains that under the executive order, the name "Department of War" will serve as a "secondary title" for the Department of Defense.
According to the fact sheet, the order will also authorize Defense Department officials to substitute the word "war" into their titles. For example, the Secretary of Defense could use the title Secretary of War.
Secretary of Defense Pete Hegseth appeared to acknowledge the change in a post on social media on Thursday, writing simply, "DEPARTMENT OF WAR."
President Trump had previously signaled that a change was in the works. During an appearance in the Oval Office last month, Trump said that War Department "just sounded to me better."
Trump does not have the authority to change the department's name without congressional action. The legal name was established by Congress in 1949, when it renamed the newly unified military service branches under a new "Department of Defense" following World War II.
In a statement to NPR, constitutional scholar Steve Vladeck confirmed that, while the president is free to refer to the Pentagon by whatever name he chooses, its "legal name can't change without Congress." After signing the order on Friday, Trump indicated that the administration would ask Congress to codify the change into law but also said, "I'm not sure they have to."
Almost from the country's founding, the army was overseen by the War Department, but the sprawling agency took on its current name following an act of Congress in 1949. At the time, the change marked the culmination of an effort by President Harry Truman to unify the Air Force, Army and Navy under the umbrella of a single department.
As the largest department in the U.S. government, even just changing signs, seals and titles could prove costly. In 2023, an Army official told Congress that an effort to rename only nine Army bases would cost taxpayers $39 million.
Danielle Kurtzleben and Quil Lawrence contributed to this report.
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